阅读说明：本技术 丙烯酰胺-α-烯烃共聚物、减阻剂及其制备方法 (Acrylamide-alpha-olefin copolymer, drag reducer and preparation method thereof ) 是由 余道轲 胡强 严斌 熊靓 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种丙烯酰胺-α-烯烃共聚物、减阻剂及其制备方法。该丙烯酰胺-α-烯烃共聚物具有通式(I)的结构。该丙烯酰胺-α-烯烃共聚物,m、k为1000～10000的整数,n为200～2000的整数,聚合度高,具有分子侧链种类多、分子量大的特点,因而减阻效果好,尤其适用于稠油管道输送。引入了长烷基丁二酰亚胺和羟烷基侧链,一方面使侧链结构多样化,不仅可降低减阻剂分子的立构规整性、结晶性,而且还增强了产品稳定性及其在原油等烃类介质中的溶解性以利于其使用时快速分散起效；另一方面多样化的侧链结构还可起到缓冲作用,增强减阻剂分子的柔性和抗剪切能力,使产品减阻效果显著持久。(The invention relates to an acrylamide-alpha-olefin copolymer, a drag reducer and a preparation method thereof. The acrylamide-alpha-olefin copolymer has a structure of a general formula (I). The acrylamide-alpha-olefin copolymer has m and k of integers of 1000-10000,n is an integer of 200-2000, the polymerization degree is high, and the anti-drag effect is good due to the characteristics of multiple molecular side chains and large molecular weight, and is particularly suitable for thick oil pipeline transportation. Long alkyl succinimide and hydroxyalkyl side chains are introduced, so that the side chain structure is diversified, the stereoregularity and crystallinity of drag reducer molecules can be reduced, and the product stability and the solubility of the drag reducer in hydrocarbon media such as crude oil and the like are enhanced, so that the drag reducer can be rapidly dispersed and take effect when in use; on the other hand, diversified side chain structures can also play a role in buffering, the flexibility and the anti-shearing capability of the drag reducer molecules are enhanced, and the drag reduction effect of the product is obvious and durable.)

1. An acrylamide- α -olefin copolymer having the following general formula (I):

wherein x is an integer of 1-4; m and k are integers of 1000-10000; n is an integer of 200 to 2000; r₁Selected from the group consisting of unsubstituted alkyl groups having 30 to 200 carbon atoms, cycloalkyl-substituted alkyl groups and aryl-substituted alkyl groupsOne or more of (a); r₂Is an alkyl group having 2 to 30 carbon atoms; r₃Is a saturated or unsaturated hydrocarbon group having 2 to 30 carbon atoms.

2. The acrylamide- α -olefin copolymer according to claim 1, wherein R is₁One or more selected from unsubstituted alkyl with 70-150 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl.

3. The acrylamide- α -olefin copolymer according to claim 1, wherein R is₂An alkyl group having 10 to 16 carbon atoms.

4. The acrylamide- α -olefin copolymer according to claim 1, wherein R is₃Is a saturated or unsaturated hydrocarbon group having 4 to 10 carbon atoms.

5. A method for preparing an acrylamide- α -olefin copolymer, comprising the steps of:

carrying out addition reaction on the alkenyl-containing compound and maleic anhydride to obtain a compound shown in a formula (II);

the compound of the formula (II) and polyene polyamine are subjected to amination reaction to obtain a compound of a formula (III);

carrying out amidation reaction on the compound shown in the formula (III) and acrylic acid in the presence of a polymerization inhibitor to obtain a compound shown in a formula (IV);

under the action of a catalyst, the compound of the formula (IV) is subjected to polymerization reaction with the monomer of the formula (V) and the monomer of the formula (VI) to obtain the acrylamide-alpha-olefin copolymer;

wherein the polyene polyamine has the structurex is an integer of 1-4;

the alkenyl-containing compound is selected from one or more of alpha-olefin, beta-olefin, cycloalkyl-substituted terminal olefin and aryl-substituted terminal olefin with the carbon number of 30-200;

the structures of the compounds of the formulas (II) to (IV) are as follows:

the R is₁One or more selected from unsubstituted alkyl with 30-200 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl;

the monomer of formula (V) is alpha-olefin with 4-32 carbon atoms, and the monomer of formula (VI) is alpha-olefin with 4-32 carbon atoms and substituted by hydroxyl at the end;

the catalyst is a ziegler-natta catalyst.

6. Use of the acrylamide- α -olefin copolymer according to any one of claims 1 to 4 or the acrylamide- α -olefin copolymer produced by the production method according to claim 5 for producing a drag reducer.

7. The drag reducer is characterized by comprising 90-100% of acrylamide-alpha-olefin copolymer and 0-10% of nano-additive in percentage by mass;

wherein the acrylamide-alpha-olefin copolymer is the acrylamide-alpha-olefin copolymer as defined in any one of claims 1 to 4 or the acrylamide-alpha-olefin copolymer prepared by the preparation method as defined in claim 5.

8. The drag reducer of claim 7, wherein said nanoadditive is selected from one or more of nano-graphite powder, graphene, and carbon nanotubes.

9. The drag reducer according to claim 7 or 8, wherein the acrylamide- α -olefin copolymer is 95% to 99.5% and the nanoadditive is 0.5% to 5% by mass.

10. A method of producing a drag reducing agent, comprising the steps of:

taking the components of acrylamide-alpha-olefin copolymer and nano-additive of the drag reducer of any one of claims 7-9 for later use;

freezing and crushing the acrylamide-alpha-olefin copolymer to obtain a crushed product;

uniformly mixing the crushed material with the nano auxiliary agent, the solvent and the dispersing agent to obtain drag reducer suspension;

wherein the mass ratio of the drag reducer component to the solvent to the dispersant is (20-50): (50-80): (0.1 to 1); the solvent is an alcohol mixture with 6-32 carbon atoms; the dispersing agent is at least one of octyl phenol polyoxyethylene ether OP-10 and nonyl phenol polyoxyethylene ether.

Technical Field

The invention relates to the field of functional materials, in particular to an acrylamide-alpha-olefin copolymer, a drag reducer and a preparation method thereof.

Background

With the development of the petroleum industry, the transportation amount of crude oil and various product oils in oil pipelines is increasing. The chemical additive is used for reducing the friction force of a pipeline system, and has important significance for safe transportation, improvement of transportation capacity, energy and investment saving, acceleration of development and utilization of crude oil and the like. Drag reducing agents are very effective chemical additives, and the fluidity of oil products can be improved by adding a small amount of the substances (generally measured by PPM) into pipeline fluid, so that the pressure of a pipeline is reduced, and the pipeline transportation capacity and the operation safety coefficient are improved.

Drag reducers are generally classified into two general categories, water-soluble drag reducers including Polyacrylamides (PAM), saponin seeds, and the like, and oil-soluble drag reducers including polyalphaolefins, polymethacrylates, and the like. To date, the most widely used are polyalphaolefin drag reducers, which include primarily homopolymers and copolymers of alpha olefins having molecular weights varying from millions to millions.

In practical applications, drag reducers for use in oil pipelines must meet several conditions: (1) ultra high molecular weight (10)⁶～10⁷) (ii) a (2) Non-crystalline; (3) good oil solubility; (4) good flexibility; (5) good shear resistance. ConventionalThe poly alpha-olefin drag reducer has small molecular weight, poor oil solubility and weak shearing resistance, and has a difficult and satisfactory drag reduction effect on domestic crude oil, particularly thick oil, so the research of the poly alpha-olefin drag reducer meeting the requirements of the domestic crude oil is urgent in the field.

Disclosure of Invention

Based on this, it is necessary to provide an acrylamide- α -olefin copolymer having an ultrahigh molecular weight and a high drag reduction ratio, a drag reducer, and a method for producing the same.

The invention provides an acrylamide-alpha-olefin copolymer, which has the following general formula (I):

wherein x is an integer of 1-4; m and k are integers of 1000-10000; n is an integer of 200 to 2000; r₁One or more selected from unsubstituted alkyl with 30-200 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl; r₂Is an alkyl group having 2 to 30 carbon atoms; r₃Is a saturated or unsaturated hydrocarbon group having 2 to 30 carbon atoms.

In some of these embodiments, the R₁One or more selected from unsubstituted alkyl with 70-150 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl.

In some of these embodiments, the R₂An alkyl group having 10 to 16 carbon atoms.

In some of these embodiments, the R₃Is a saturated or unsaturated hydrocarbon group having 4 to 10 carbon atoms.

The acrylamide-alpha-olefin copolymer has m and k being integers of 1000-10000, n being 200-2000, high polymerization degree, diversified side chain structures, capability of reducing the stereoregularity and crystallinity of drag reducer molecules, capability of improving the molecular weight and simultaneously ensuring good oil solubility and anti-shearing capability, excellent drag reduction effect and particular suitability for thick oil pipeline transportation.

The invention also provides a preparation method of the acrylamide-alpha-olefin copolymer, which comprises the following steps:

carrying out addition reaction on the alkenyl-containing compound and maleic anhydride to obtain a compound shown in a formula (II);

the compound of the formula (II) and polyene polyamine are subjected to amination reaction to obtain a compound of a formula (III);

carrying out amidation reaction on the compound shown in the formula (III) and acrylic acid in the presence of a polymerization inhibitor to obtain a compound shown in a formula (IV);

under the action of a catalyst, the compound of the formula (IV) is subjected to polymerization reaction with the monomer of the formula (V) and the monomer of the formula (VI) to obtain the acrylamide-alpha-olefin copolymer;

wherein the polyene polyamine has the structurex is an integer of 1-4;

the alkenyl-containing compound is selected from one or more of alpha-olefin, beta-olefin, cycloalkyl-substituted terminal olefin and aryl-substituted terminal olefin with the carbon number of 30-200;

the structures of the compounds of the formulas (II) to (IV) are as follows:

the R is₁One or more selected from unsubstituted alkyl with 30-200 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl;

the monomer of formula (V) is alpha-olefin with 4-32 carbon atoms, and the monomer of formula (VI) is alpha-olefin with 4-32 carbon atoms and substituted by hydroxyl at the end;

the catalyst is a ziegler-natta catalyst.

The invention also provides the application of the acrylamide-alpha-olefin copolymer in preparing a drag reducer.

The invention also provides a drag reducer which comprises 90-100% of acrylamide-alpha-olefin copolymer and 0-10% of nano-additive by mass percent.

The drag reducer comprises acrylamide-alpha-olefin copolymer and nano auxiliary agent with specific content. From the structure of the drag reducer molecule, the introduction of the long-chain succinimide and the hydroxyalkyl side chain diversifies the side chain structure, reduces the stereoregularity and crystallinity of the drag reducer molecule, enhances the stability of the product and the solubility of the product in hydrocarbon media such as crude oil and the like, and is beneficial to rapid dispersion and effect during use. On the other hand, the anti-drag agent can play a role in buffering, the anti-shearing capability of the molecules of the anti-drag agent is enhanced, and the anti-drag effect of the product is obvious and durable. The introduction of the nano-additive in the formula enhances the rigidity of a polymer skeleton of the drag reducer, promotes the stretching and shearing resistance of molecular chains of the drag reducer in a medium, enables the product to be quickly dissolved into a crude oil medium in use, has excellent drag reduction effect, and is particularly suitable for thick oil pipeline transportation.

In some of these embodiments, the nanoadditive is selected from one or more of nano-graphite powder, graphene, and carbon nanotubes.

In some embodiments, the acrylamide- α -olefin copolymer is 95% to 99.5% and the nanoadditive is 0.5% to 5%.

The invention also provides a preparation method of the drag reducer, which comprises the following steps:

taking the components of the drag reducer, namely acrylamide-alpha-olefin copolymer and nano-additive for later use;

freezing and crushing the acrylamide-alpha-olefin copolymer to obtain a crushed product;

uniformly mixing the crushed material with the nano auxiliary agent, the solvent and the dispersing agent to obtain drag reducer suspension;

wherein the mass ratio of the drag reducer component to the solvent to the dispersant is (20-50): (50-80): (0.1 to 1); the solvent is an alcohol mixture with 6-32 carbon atoms; the dispersing agent is at least one of octyl phenol polyoxyethylene ether OP-10 and nonyl phenol polyoxyethylene ether.

The drag reducer of the present invention has the following major advantages over conventional drag reducers:

(1) the introduction of long-chain succinimide and hydroxyalkyl side chains diversifies the side chain structure, reduces the stereoregularity and crystallinity of drag reducer molecules, enhances the solubility of the drag reducer molecules in hydrocarbon media such as crude oil and the like, and is beneficial to quick dispersion and effect in the crude oil during use.

(2) The introduction of hydroxyl on the side chain enhances the intermiscibility of the hydroxyl with an alcohol solvent, is beneficial to forming a stable suspension product, and can be quickly dissolved into a crude oil medium to improve the drag reduction effect when in use.

(3) The side chain long-chain succinimide can also play a role in buffering, the anti-shearing capability of the drag reducer molecules is enhanced, and the drag reduction effect of the product is obvious and durable.

(4) The polymerization degree and the drag reduction effect of the drag reducer can be improved by adopting a novel Ziegler-Natta catalyst.

(5) The introduction of the nano assistant in the formula enhances the rigidity of a polymer skeleton of the drag reducer, promotes the stretching and anti-shearing performance of molecular chains of the drag reducer in a medium, enables the product to be quickly dissolved into a crude oil medium when in use, and improves the drag reduction effect.

Detailed Description

In order that the invention may be more fully understood, reference will now be made to the following description. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Starting from the design optimization of the drag reducer molecules, the invention firstly selects monomers with different chain length structures, in particular to monomers with long chain succinimide base structures, can reduce the stereoregularity and crystallinity of the drag reducer molecules, enhance the solubility of the drag reducer molecules in hydrocarbon media such as crude oil and the like, and enhance the anti-shearing capability of the drag reducer molecules through the buffering effect of long side chains. Secondly, the molecular polymerization degree and molecular weight of the drag reducer can be improved by selecting a novel Ziegler-Natta catalyst. In addition, hydroxyl is introduced into the molecular structure, so that the compatibility of the alcohol solvent and the hydroxyl can be enhanced, a stable suspension product is formed under the coordination of other auxiliary agents in the later period, and the hydroxyl can be quickly dissolved into a crude oil medium in use to improve the drag reduction effect. In addition, the ashless nano-additive can be added according to different crude oil requirements in the post-treatment of the polymer, so that the rigidity of a high molecular framework is enhanced, the stretching and shearing resistance of a molecular chain of the drag reducer in a medium is promoted, and the using effect of the product is improved.

One embodiment of the present invention provides an acrylamide- α -olefin copolymer having the following general formula (I):

wherein x is an integer of 1-4; m and k are integers of 1000-10000; n is an integer of 200 to 2000; r₁One or more selected from the group consisting of an unsubstituted alkyl group having 30 to 200 carbon atoms, a cycloalkyl-substituted alkyl group having 30 to 200 carbon atoms and an aryl-substituted alkyl group having 30 to 200 carbon atoms; r₂Is an alkyl group having 2 to 30 carbon atoms; r₃Is a saturated or unsaturated hydrocarbon group having 2 to 30 carbon atoms.

Specifically, the cycloalkyl-substituted alkyl group is selected from one or more of a cyclopropyl-substituted alkyl group, a cyclobutane-substituted alkyl group, a cyclopentyl-substituted alkyl group and a cyclohexyl-substituted alkyl group; the aryl-substituted alkyl is selected from one or more of phenyl-substituted alkyl and naphthyl-substituted alkyl.

In some of these embodiments, R₁One or more selected from the group consisting of unsubstituted alkyl groups having 70 to 150 carbon atoms, cycloalkyl-substituted alkyl groups having 70 to 150 carbon atoms and aryl-substituted alkyl groups having 70 to 150 carbon atoms.

In some of these embodiments, R₂An alkyl group having 10 to 16 carbon atoms.

In some of these embodiments, R₃Is a saturated or unsaturated hydrocarbon group having 4 to 10 carbon atoms.

The acrylamide-alpha-olefin copolymer has the advantages that m and k are integers of 1000-10000, n is an integer of 200-2000, the polymerization degree is high, the side chain structure is diversified, the stereoregularity and crystallinity of drag reducer molecules can be reduced, the molecular weight is improved, the drag reducer has good oil solubility and anti-shearing capability, the drag reduction effect is excellent, and the acrylamide-alpha-olefin copolymer is particularly suitable for thick oil pipeline transportation.

An embodiment of the present invention further provides a method for preparing the acrylamide- α -olefin copolymer, including the following steps S11 to S14.

Step S11: carrying out addition reaction on the alkenyl-containing compound and maleic anhydride to obtain a compound shown in a formula (II);

step S12: carrying out amination reaction on the compound of the formula (II) and polyene polyamine to obtain a compound of a formula (III);

step S13: carrying out amidation reaction on the compound shown in the formula (III) and acrylic acid in the presence of a polymerization inhibitor to obtain a compound shown in a formula (IV);

step S14: under the action of a catalyst, carrying out polymerization reaction on a compound shown in a formula (IV), a monomer shown in a formula (V) and a monomer shown in a formula (VI) to obtain an acrylamide-alpha-olefin copolymer;

wherein the polyene polyamine has the structurex is an integer of 1-4; the alkenyl-containing compound is one or more selected from alpha-olefin, beta-olefin, cycloalkyl-substituted terminal olefin and aryl-substituted terminal olefin with 30-200 carbon atoms; the structures of the compounds of formulae (II) to (IV) are as follows:

R₁one or more selected from unsubstituted alkyl with 30-200 carbon atoms, alkyl substituted by cycloalkyl and alkyl substituted by aryl; the monomer of formula (V) has 4 to 32 carbon atomsThe alpha-olefin of the formula (VI) is a hydroxyl-terminated alpha-olefin with 4-32 carbon atoms.

In some of these embodiments, the molar ratio of the alkenyl-containing compound to maleic anhydride in step S11 is 1: (1-3).

In some of these embodiments, the conditions for the addition reaction in step S11 are: reacting for 4-72 h under the conditions of normal pressure or pressurization at the temperature of 170-240 ℃ in the nitrogen atmosphere. Specifically, the reaction time is related to the alkenyl-containing compound and the reaction pressure, and the alkenyl-containing compound has a large molecular weight, a low reaction pressure and a long reaction time; the alkenyl-containing compound has a small molecular weight and a high reaction pressure, and thus the reaction time is short.

In some of these embodiments, the addition reaction of the alkenyl-containing compound and maleic anhydride in step S11 is conducted under solvent conditions. Preferably, the solvent is selected from at least one hydrocarbon solvent having a boiling point of 170 ℃ to 300 ℃. Further, the molar ratio of the alkenyl-containing compound, maleic anhydride and solvent is 1: (1.5-2.5): (0-8).

In some of these embodiments, the molar ratio of the compound of formula (II) to the polyene polyamine of step S12 is 1: (0.8 to 1.2).

In some of these embodiments, the conditions of the amination reaction in step S12 are: reacting for 2-24 h under the condition of normal pressure at the temperature of 100-180 ℃ in the nitrogen atmosphere.

In some of these embodiments, the amination of the compound of formula (II) with a polyene polyamine in step S12 is carried out under solvent conditions. Preferably, the solvent is selected from at least one of aromatic hydrocarbon solvents and petroleum ether solvents. Further, the molar ratio of the compound of formula (II), the polyene polyamine and the solvent is 1: (1-1.1): (0-8).

In some embodiments, the molar ratio of the compound of formula (III), acrylic acid and polymerization inhibitor in step S13 is 1 (0.8-1.2): (0.001-0.005).

In some of these embodiments, the polymerization inhibitor is selected from one or more of tert-butyl catechol, 3, 5-dimethylaniline, phenothiazine, methyl hydroquinone.

In some of these embodiments, the conditions of the amidation reaction in step S13 are: reacting for 2-24 h under the atmosphere of nitrogen and under the temperature of 0-110 ℃ and normal pressure.

In some of these embodiments, the molar ratio of catalyst, compound of formula (IV), monomer of formula (V), and monomer of formula (VI) is (0.01-0.5): 1: (5-20): (0.5 to 10).

In some of these embodiments, the catalyst includes a procatalyst, a cocatalyst and a synergist. The main catalyst is selected from at least one of chlorides or other complexes of transition metals such as titanium, vanadium, zirconium and the like, and the cocatalyst is selected from trimethylaluminum, triethylaluminum, triisobutylaluminum, monobromodiethylaluminum, methylaluminoxane, ethylaluminoxane and organic boride (B (C)₆F₅)₃) At least one synergist selected from diisobutyl phthalate, ethyl benzoate, diisobutyl 2, 3-diisopropylsuccinate, 2, 4-pentanediol dibenzoate, 2, 4-trimethyl-1, 3-pentanediol bibenzoate, 3-ethyl-2, 5-pentanedione, and 3-diphenylpropanedione.

In some of these embodiments, the procatalyst: the molar ratio of the (cocatalyst + synergist) is 1: (1.5-6).

In some embodiments, step S14 is performed at a temperature of-20 ℃ to 30 ℃ for 24h to 120 h.

An embodiment of the present invention further provides an application of the acrylamide- α -olefin copolymer in preparing a drag reducer.

The invention also provides a drag reducer, which comprises 90-100% of acrylamide-alpha-olefin copolymer and 0-10% of nano auxiliary agent by mass percent.

The drag reducer comprises acrylamide-alpha-olefin copolymer and nano auxiliary agent with specific content. From the structure of the drag reducer molecule, the introduction of the long-chain succinimide and the hydroxyalkyl side chain diversifies the side chain structure, reduces the stereoregularity and crystallinity of the drag reducer molecule, enhances the stability of the product and the solubility of the product in hydrocarbon media such as crude oil and the like, and is beneficial to rapid dispersion and effect during use. On the other hand, the anti-drag agent can play a role in buffering, the anti-shearing capability of the molecules of the anti-drag agent is enhanced, and the anti-drag effect of the product is obvious and durable.

The introduction of the nano assistant in the formula enhances the rigidity of a polymer skeleton of the drag reducer, promotes the stretching and anti-shearing performance of molecular chains of the drag reducer in a medium, enables the product to be quickly dissolved into a crude oil medium in use, and improves the drag reduction effect.

In some of these embodiments, the nanoadditive is selected from one or more of nano-graphite powder, graphene, and carbon nanotubes.

In some embodiments, the acrylamide-alpha-olefin copolymer is 95 to 99.5% and the nano-additive is 0.5 to 5% by mass.

An embodiment of the present invention further provides a method for preparing a drag reducer, including the following steps S21 to S23.

Step S21: taking the components of the drag reducer, namely acrylamide-alpha-olefin copolymer and nano-additive for later use;

step S22: freezing and crushing the acrylamide-alpha-olefin copolymer to obtain a crushed product;

step S23: and uniformly mixing the crushed material with a nano assistant, a dispersing agent and a solvent to obtain a drag reducer suspension.

In some of these embodiments, the step of freeze-pulverizing the acrylamide- α -olefin copolymer is performed at a temperature of 0 to-50 ℃.

Specifically, in step S23, the mass ratio of the drag reducer component, the solvent and the dispersant is (20-50): (50-80): (0.1 to 1).

In some embodiments, the solvent used in step S23 is an alcohol mixture having 6 to 32 carbon atoms. The dispersant is at least one of octyl phenol polyoxyethylene ether OP-10 and nonyl phenol polyoxyethylene ether. The polyoxyethylene nonyl phenyl ether is at least one selected from NP-4, NP-7 and NP-10.

Specifically, the alcohol mixture having 6 to 32 carbon atoms in the present embodiment is understood to be a mixture of at least one of alcohols having 6 to 10 carbon atoms and at least one of alcohols having 20 to 32 carbon atoms.

The preparation method of the drag reducer has simple process and is easy to realize industrial production. The prepared suspension has good product stability, is convenient to store and transport, and is convenient to add the agent.

The following are specific examples.

Example 1:

the process for preparing the polymeric drag reducer of this example includes the steps of:

the method comprises the following steps: sequentially adding 1mol of high-activity polyisobutylene with the molecular weight of 1000, 1.2mol of maleic anhydride and 8mol of tetramethylbenzene into a reaction kettle, uniformly stirring, heating to 190 ℃ under the protection of nitrogen, stirring for reacting for 36 hours, cooling to room temperature, washing with water and drying to obtain a polyisobutenyl succinic anhydride intermediate solution for later use.

Step two: and (3) adding the solution of the polyisobutenyl succinic anhydride intermediate with the effective content of 1mol and 1mol of ethylenediamine into a reaction kettle in sequence, uniformly stirring, reacting for 4 hours at 110 ℃ under the protection of nitrogen, and then distilling under reduced pressure to remove the solvent and other low-boiling-point substances to obtain the polyisobutenyl succinimide for later use.

Step three: adding 1mol of the polyisobutenyl succinimide, 1.1mol of acrylic acid, 0.005mol of p-tert-butylcatechol polymerization inhibitor and 8mol of toluene into a reaction kettle, stirring at 80 ℃ for reaction for 6 hours, washing with alkali, drying, and distilling under reduced pressure to remove the solvent to obtain the polyisobutenyl succinimide acrylamide for later use.

Step four: under the protection of nitrogen, 1mol of the polyisobutenyl succinimidyl acrylamide monomer, 7.5mol of alpha-dodecene and 1mol of 2, 7-octadiene-1-ol are fully mixed, cooled to-10 ℃, and then 0.01mol of TiCl is added₄/MgCl₂0.015mol of triisobutyl aluminum and 0.005mol of 2, 3-diisopropyl diisobutyl succinate, and reacting for 48 hours at the temperature of minus 10 +/-3 ℃ to obtain the acrylamide-alpha-olefin copolymer for later use.

Step five: freezing the copolymerization product obtained in the fourth step to-40 ℃ and crushing. Uniformly mixing 45 parts of crushed material, 45.2 parts of heptanol, 10 parts of triacontanol and 0.8 part of NP-10 surfactant by 100 parts by mass to obtain a drag reducer finished product.

Example 2:

the process for preparing the polymeric drag reducer of this example includes the steps of:

the method comprises the following steps: sequentially adding 1mol of high-activity polyisobutylene with the molecular weight of 500, 2mol of maleic anhydride and 6mol of tetramethylbenzene solvent into a reaction kettle, uniformly stirring, heating to 200 ℃ under the protection of nitrogen, stirring for reaction for 12 hours, cooling to room temperature, washing with water and drying to obtain a polyisobutenyl succinic anhydride intermediate solution for later use.

Step two: and (3) sequentially adding the polyisobutenyl succinic anhydride intermediate solution with the effective content of 1mol and 1.1mol of diethylenetriamine into a reaction kettle, uniformly stirring, reacting for 6 hours at 100 ℃ under the protection of nitrogen, and then carrying out reduced pressure distillation to remove the solvent and unreacted substances to obtain the polyisobutenyl succinimide for later use.

Step three: adding 1mol of the polyisobutylene succinimide, 1.0mol of acrylic acid, 0.001mol of hydroquinone polymerization inhibitor and 3mol of toluene into a reaction kettle, stirring and reacting for 8 hours at 60 ℃ under the protection of nitrogen, washing with water, drying, and distilling under reduced pressure to remove the solvent to obtain the polyisobutylene succinimide acrylamide for later use.

Step four: under the protection of nitrogen, 1mol of the polyisobutenyl succinimide monomer, 20mol of alpha-octadecene and 0.5mol of 2, 7-octadiene-1-ol are fully and uniformly mixed, cooled to-15 ℃, and then 0.02mol of TiCl is added₄0.1mol of methylaluminoxane, 0.01mol of 3-ethyl-2, 5-pentanedione and the temperature of 15 +/-5 ℃ for 60 hours to obtain the acrylamide-alpha-olefin copolymer for later use.

Step five: and (4) continuously cooling the copolymerization product obtained in the step four to-50 ℃, and crushing in a refrigerating sample crusher. And uniformly mixing 39 parts of the crushed material, 1 part of carbon nano tube, 39.5 parts of isooctanol, 20 parts of triacontanol and 0.5 part of OP-10 surfactant by mass according to 100 parts of the mass to obtain a drag reducer finished product.

Example 3:

the procedure for the preparation of the polymeric drag reducing agent of this example was the same as that of example 1 except that in step one, highly reactive polyisobutylene having an average molecular weight of 2000 was used, the solvent used in step five, heptanol, was changed to octanol, and the dispersant NP-10 was changed to NP-4.

Example 4:

the polymeric drag reducer of this example was prepared using the same procedure as in example 1, except that the polyene polyamine used in step two was diethylenetriamine.

Example 5:

the procedure for the preparation of the polymer drag reducer of this example was the same as in example 1 except that the amount of enol used in step IV was 1.3 mol.

Examples 6 to 8:

the preparation steps of the polymer drag reducer in this embodiment are the same as those in embodiment 1, except that in step five, in embodiments 6 to 8, 1% of nano graphite powder, 5% of graphene, and 3% of carbon nanotubes are added and fully mixed by mass.

Example 9:

the polymer drag reducer of this example was prepared using the same procedure as in example 1, except that the α -dodecene used in step four was increased from 5mol to 10 mol.

Example 10:

the procedure for the preparation of the polymer drag reducing agent of this example was the same as in example 1 except that the polyisobutenyl succinimidyl acrylamide monomer used in step four was increased from 1mol to 1.5 mol.

Comparative example 1:

under the protection of nitrogen, setting the temperature of a reaction kettle at-5 ℃, adding 20mol of alpha-dodecene into the polymerization reaction kettle for fully mixing, and then adding 0.01mol of TiCl₄/MgCl₂And 0.03mol of triethyl aluminum, reacting for 72 hours, sealing the product after the reaction is finished, fully freezing at the temperature of minus 40 ℃, and crushing in a refrigerating sample crusher. Uniformly mixing 45 parts of crushed material, 45.2 parts of heptanol, 10 parts of triacontanol and 0.8 part of NP-10 surfactant by 100 parts by mass to obtain a drag reducer finished product.

Comparative example 2:

under the protection of nitrogen, setting the temperature of a reaction kettle at-5 ℃, adding 2mol of alpha-octene and 18mol of alpha-dodecene into the polymerization reaction kettle, fully mixing uniformly, and then adding 0.01mol of TiCl₄/MgCl₂0.03mol of triethylaluminum, 0.01mol of 2, 3-diisopropylamberDiisobutyl sulfate reacts for 72 hours, and after the reaction is finished, the product is sealed and fully frozen at the temperature of minus 40 ℃ and then crushed in a refrigerating sample crusher. Uniformly mixing 45 parts of crushed material, 45.2 parts of heptanol, 10 parts of triacontanol and 0.8 part of NP-10 surfactant by 100 parts by mass to obtain a drag reducer finished product.

Comparative example 3:

the procedure for the preparation of the polymeric drag reducer of this comparative example was the same as example 1 except that in step one, the highly reactive polyisobutylene with a molecular weight of 1000 was replaced with 1-tetracosene.

Comparative example 4:

the procedure for the preparation of the polymeric drag reducing agent of this comparative example is the same as example 1 except that in step four, the catalyst enhancer, diisobutyl 2, 3-diisopropylsuccinate, is not added.

The main performance (molecular weight, drag reduction effect, shear stability) comparison standards and equipment models of drag reducers are as follows: (1) molecular weight was determined by Waters-Breeze GPC chromatography; (2) the shear stability is tested according to SH/T0505-92 standard with ASTM D2603-01 equipment; (3) the Drag reduction effect is tested according to SY/T6578-₀—△P_r)/△P₀X 100% of the formula, wherein, Δ P₀The friction resistance pressure drop, Pa, at two ends of the pipeline when the drag reducer is not added; delta P_rThe pressure drop is the friction resistance pressure drop Pa at two ends of the pipeline at the same flow (flow speed) after the agent is added.

The molecular weight, drag reduction performance, shear performance and the like were measured in each of examples and comparative examples, commercially available 1 (oily drag reducer Flowi-11, Prov. Nature chemical technology Co., Ltd., corridor, Ltd.), and commercially available 2 (dry powder drag reducer, DR-3 Puyang, Huiyuan Industrial Co., Ltd.), and the results are shown in Table 1. The additive amount of each drag reducer was 20 ppm. The shear resistance is evaluated by the ratio of the drag reduction rate after shearing to the original drag reduction rate, the larger the ratio, the better the shear resistance.

TABLE 1

As is clear from Table 1, the molecular weight of the acrylamide- α -olefin copolymers of examples 1, 3 to 5, 9 and 10 was 7.6X 10⁶～1.25×10⁷And has an ultra-high molecular weight. The drag reduction ratios of examples 1, 3 to 5, 9 and 10 are 49.7 to 66.1 percent, and the drag reduction ratios are obviously higher than those of comparative examples 1 to 4 and commercially available drag reduction agents 1, which shows that the drag reduction effects of the ultra-high molecular weight acrylamide-alpha-olefin copolymer drag reduction agents of examples 1, 3 to 5, 9 and 10 are good.

Comparing the preparation steps and experimental results of example 1 and comparative example 3, it can be found that the use of polyisobutylene with high activity has higher shear resistance than that of drag reducer molecules synthesized by conventional olefins, and comparing the preparation steps and experimental results of example 9 and example 10, it can be found that the use of polyisobutylene succinimide monomer with high proportion can effectively increase the drag reducer effect than that of common alpha olefin with high proportion, because the introduction of polyisobutylene succinimide increases the side chain diversification, and because polyisobutylene succinimide monomer can enhance the shear resistance of products, thereby improving the drag reduction effect of products. The higher the polymer terminal polyisobutylene succinimide monomer ratio is, the more obvious the resistance reduction effect is improved. This can also be confirmed from a comparison of the results of comparative example 5 and comparative example 2: the drag reducer with the same average molecular weight has better drag reduction effect by using synthesized drag reducer molecules with high-activity polyisobutylene and high-carbon enol as starting points. Comparing the preparation steps and experimental results of example 1 with example 5, it can be seen that the drag reducer starting from the slightly higher ratio of the carbon enol has a higher original drag reduction effect, because increasing the ratio of the enol can improve the stability of the drag reducer suspension, and thus the drag reduction effect. In summary, the introduction of various side chain structures into the drag reducer polymer molecule helps to improve the overall properties (dispersibility, ductility, etc.) of the drag reducer molecule, and especially the shear resistance can be significantly improved.

Comparing the preparation steps and experimental results of example 1 and comparative example 4 (or comparative example 1 and comparative example 2), it can be found that the addition of the third component catalytic synergist is helpful for improving the polymerization degree of the drag reducer molecules and further improving the drag reduction effect.

Comparing the preparation steps of example 1 with those of examples 6 to 8 with the experimental results, it can be found that the shear resistance is greatly improved after the nano-additive is added, the original drag reduction rate is obviously improved, and the nano-additive has a certain positive significance for improving the shear resistance of the polymer drag reduction agent. In addition, the experimental results of comparing examples 2 and 6-8 with those of the commercial 2 dry powder type drag reducer with the addition of the auxiliary agent show that the drag reduction effect is significantly higher than that and the shear resistance of the conventional product after the addition of the nano auxiliary agent.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.